When you eat a lot of processed or cooked foods, your immune system’s white blood cells flood the gut so they’re not available to fight invading infections elsewhere, so boost the amount of raw fruit and veg you eat.

“Probiotics can help boost your immune system,” says Dr Ashton Harper. “A gut equipped with an army of probiotics can directly fight pathogens, which produce bacteria-specific molecules similar to antibiotics.

"Multi-strain probiotics, which supply a diverse range of bacterial species, are likely to offer greater utility in boosting immunity and reducing severity and duration of the common cold.”

Foods you need to eat to stamp out that cold

Want to keep illness at bay? These are the cold-fighting foods you need to eat.

How to get rid of a cold fast: Eating fresh ginger could help symptoms

Vitamin D

Public Health England advised everybody to take daily vitamin D supplements during autumn and winter, as sunlight hours - the biggest natural source of the vitamin - was reduced during the seasons.

A new study found taking vitamin D in supplement form protects against acute respiratory infections.

Lead researcher Professor Adrian Martineau, from QMUL, said: “Assuming a UK population of 65 million, and that 70% have at least one acute respiratory infection each year, then daily or weekly vitamin D supplements will mean 3.25 million fewer people would get at least one acute respiratory infection a year.”

Ginger

To many it’s a simple plant stem, delicious cooked in biscuits or wrapped in chocolate, but actually could it be the hero we’re all searching for when it comes to cold and flu?

Will Hawkins, nutritionist at Push Doctor, an online GP service, told Express.co.uk: “Ginger can protect you against the virus that causes respiratory tract infections.

“In other words, it could reduce your chances of getting a cold in the first place.”

Just a thumb-sized piece of ginger a week should be enough to experience the benefits.

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How to get rid of a cold fast: Washing your hands thoroughly would help prevent the spread of germs

Be positive and go for a walk

According to US researchers, positive people who don’t over-react and are enthusiastic about life are less likely to catch a cold.

The research group believe a positive mental outlook lowers levels of stress hormone, cortisol, in the body.

Similarly, people who do a moderate level of exercise in fresh air five days a week cut their chances of getting a cold by almost 50 per cent.

Wash your hands

Bugs only enter your system after you’ve touched an infected surface or person, and then touched your nose, eyes or mouth.

Washing your hands thoroughly with soap and water at every opportunity will lower your risk of catching an infection.

However, also making sure you’re not spreading germs when you’re ill - catching a sneeze into a tissue etc - is imperative.

Elizabeth Wall, nutritionist at Holland & Barrett, said: “Not only can cold viruses enter the body through contact with infected droplets by touch, they can also be launched into the air through coughs and sneezes.”